Had the idea the other day for a unique hybrid, Spimetrosaurus Rex. It started with T-Rex and Spinosaurus, because I thought it would be cool to have the villians of the original triology in a single package. At this level it would be a legendary, Spinosaurus Rex, with high damage and a bleed attack. Then in the unique level you would add a menber of the dimetrodon family to the mix to give it that coveted immunity. I draw a sketch of what it should look like and with the bulk of the T-Rex and the combined sails of the spinosaurus and Dimetrodon it looked downright awesome. Although I drew it on a napkin at work and somebody threw it away.
Just a thought, not sure if they take dinosaur suggestions or not.